Princeton University

School of Engineering & Applied Science

Semantically-Secured Message-Key Trade-off over Wiretap Channels with Random Parameters

Shlomo Shamai (Shitz), Technion-Israel Institute of Technology
B205 Engineering Quadrangle
Monday, July 30, 2018 - 4:00pm

Two fundamental questions in physical layer security are those related to the best achievable transmission rate of a secret message (SM) over a noisy channel, and the highest attainable secret key (SK) rate that distributed parties can agree upon. We study the trade-off between SM and SK rates simultaneously achievable over a state-dependent wiretap channel with non-causal channel state information (CSI) at the encoder. This model subsumes all other instances of CSI availability as special cases, and calls for an efficient utilization of the state sequence both for reliability and security purposes. We derive an inner bound on the SM-SK capacity region based on a novel superposition coding scheme.
This inner bound improves upon the previously best known SM-SK trade-off result by Prabhakaran et al, and to the best of our knowledge, upon all other existing lower bounds for either SM or SK for this setup.
The results are derived under the strict semantic-security metric that requires negligible information leakage for all message-key distributions. The achievability proof uses the likelihood encoder and the strong soft-covering lemma for superposition codes. We conclude by a short outlook.
Joint work with: A. Bunin (Technion-Israel Institute of Technology), Z. Goldfeld (MIT), H.H. Permuter (Ben-Gurion University, Israel), P.W. Cuff (Renaissance Technologies) and P.  Piantanida (CentralSupelec). The work was supported by the European Union's Horizon 2020 Research and Innovation Programme, grant agreement no. 694630.
Bio:  Shlomo Shamai (Shitz) received the B.Sc., M.Sc., and Ph.D. degrees in electrical engineering from the Technion---Israel Institute of Technology, in 1975, 1981 and 1986 respectively.
During 1975-1985, he was with the Communications Research Labs, in the capacity of a Senior Research Engineer. Since 1986 he is with the Department of Electrical Engineering, Technion---Israel Institute of Technology, where he is now a Technion Distinguished Professor, and holds the William Fondiller Chair of Telecommunications. His research interests encompass a wide spectrum of topics in information theory and statistical communications.
Dr. Shamai (Shitz) is an IEEE Fellow, an URSI Fellow, a member of the Israeli Academy of Sciences and Humanities and a foreign member of the US National Academy of Engineering. He is the recipient of the 2011 Claude E. Shannon Award, the 2014 Rothschild Prize in Mathematics/Computer Sciences and Engineering and the 2017 IEEE Richard W. Hamming Medal.